/**
 *  Creates `HTMLStyleElement`, inserts it into DOM and then inserts CSS rules into the stylesheet.
 *  If style element already exists, nothing happens.
 */
export declare function configureWebLayoutAnimations(): void;
export declare function insertWebAnimation(animationName: string, keyframe: string): void;
export declare function scheduleAnimationCleanup(animationName: string, animationDuration: number): void;
export declare function areDOMRectsEqual(r1: DOMRect, r2: DOMRect): boolean;
